1. Field of the invention
The invention relates to an implant for bone and tooth root prostheses, the implant being composed of a core and a matrix having particles embedded therein. Joint implants are addressed in particular. The invention further relates to a method using the implant according to the invention.
2. Background of the Art
It is known that metallic, ceramic and bonded fiber implants are being used, or their use is being developed as substitutes for bones and joints or tooth roots. Some of the materials employed are bio-inert, some are biocompatible. In many cases it is desired to provide coatings of inorganic and organic substances having bioactive effects. These coating materials are more or less resorbable and are dissolved by the body in a few years at the latest. Since growth and attachment by bone growth occurs only at the surface of the implant, loosening phenomena occur in all known implant materials.
For tooth root implants the state of the art permits only a rigid connection between implant and jaw bone. There are no dental implants which are adapted to natural conditions. Therefore, complicated structures to dampen pressure peaks are required for present-day dental implants to prevent the implant from breaking out of the jaw bone. Due to the wrong stresses on the jaw bone, the latter also decomposes if commercially available implants are employed.
Implants are also known which are made of porous, tissue compatible metals, plastic fibers or composite metals and in which the outer layers contain a plastic matrix with embedded inorganic, resorbable particles. However, in connection with these prior art implants it has also been found that an uninterfered-with bond between bone and fiber material is impossible. The consequence is that after a certain period of time, the implants must be exchanged for new ones which usually requires, in a then necessary second surgical procedure, further excavation of bone, e.g. longer shafts or larger hip sockets.
It is therefore the object of the invention to provide an implant which assures a permanent and lifetime connection, or anchorage, of the implant with the natural bone and thus reduces or completely avoids repeated surgery for implantations. It is a further object of the present invention to provide a suitable method which employs implants that accomplish this task.